Immunohistochemistry (IHC) refers to the process of detecting antigens (e.g., proteins) in cells of a tissue section by exploiting specific antibody-antigen interactions using labeled antibodies or other ligands. IHC is also widely used in basic research to understand the distribution and localization of biomarkers and differentially expressed proteins in different parts of a biological tissue. Applications include diagnostics, pharmaceutical development and research.
For example, samples can be prepared on individual slides, or multiple samples can be arranged on a single slide for comparative analysis, such as with tissue microarrays. IHC slides can be processed and stained, and then viewed by either light or fluorescence microscopy. The main output of the tissue staining is for optical or fluorescence imaging as well as archival and storage of stained tissue.
Currently there are high and moderate volume automated systems available for IHC. Manual systems are available for the occasional research, which are labor intensive and require many pipetting and dip/soak washing steps. These steps include slide mounted tissue washing, blocking, primary, secondary and tertiary antibody introduction, covered incubation, as well multiple washes and rinses in between each step. This complex, lengthy handling process is prone to errors, which can ultimately compromise the result.
It would be desirable to provide a system that eliminates drawbacks of the conventional systems, allowing, for example, consistent fluid delivery to the sample, recovery of precious reagents, minimum slide handling (no transfer of slides between different baths) and carrying out of multiple concurrent assays.